Mustaine, who left Metallica in 1983, said he was contacted by James Hetfield two years ago about the possibility of returning to their earliest songs. "We were going to officially release the No Life 'til Leather demo as a record, with 27 tracks, pics, the whole enchilada," Mustaine wrote on Twitter, "and the talks broke down because Lars wanted credit on two songs I wrote every note and word to. I have the texts. I passed."

Back in 2015, when Metallica announced a limited-edition cassette-only reissue of No Life 'til Leather for Record Store Day, it seemed the demo was next in line for an expanded look back. "It's time for us to put out some next-level reissues and do the song and dance of the catalog that everyone else has done – the U2s and the Led Zeppelins and the Oasises," Ulrich told Rolling Stone. "Instead of starting with Kill 'Em All in 1983, we figured we'd go back another two years to when the band was formed in 1981."

Many of the tracks on No Life 'til Leather were later updated for Kill 'Em All, though the LP contains several exclusive songs, including "No Remorse," "The Four Horsemen" and "Whiplash." It's been widely bootlegged over the years, and was even portrayed (with tacked on crowd noise) as an early live recording in one particularly egregious knock off.